1020200209961 has 2 divisors, whose sum is σ = 1020200209962. Its totient is φ = 1020200209960.

The previous prime is 1020200209949. The next prime is 1020200209981. The reversal of 1020200209961 is 1699020020201.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1019179087936 + 1021122025 = 1009544^2 + 31955^2 .

It is a cyclic number.

It is not a de Polignac number, because 1020200209961 - 2³⁰ = 1019126468137 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1020200209981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510100104980 + 510100104981.

It is an arithmetic number, because the mean of its divisors is an integer number (510100104981).

Almost surely, 2^{1020200209961} is an apocalyptic number.

It is an amenable number.

1020200209961 is a deficient number, since it is larger than the sum of its proper divisors (1).

1020200209961 is an equidigital number, since it uses as much as digits as its factorization.

1020200209961 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 32.

The spelling of 1020200209961 in words is "one trillion, twenty billion, two hundred million, two hundred nine thousand, nine hundred sixty-one".